I believe the "pass through" capability is simply to allow it to sit between your cable/satellite box and your TV. When commanded, it will encode the signal (I think in either H.264 or VC-1) and pass that stream via USB to the computer. The encoder chip just leeches the signal from the component pass through.

When you're not recording, you wouldn't want to disconnect it from the cable/satellite box (and re-connect the STB to the TV) just to watch live TV. Or for that matter, be required to have an expensive, dedicated cable/satellite HD box just for recording. Most people would want something that just sits between the (non Knoppmyth) STB and the TV. Hook it up once and forget it.

And I'm also sure that it does the "pass through" electrically, all the time, regardless of if it's recording or not. I'd bet it even works if you disconnect the power to the HD PVR.

This device had no Decoding capabilities at all, only Encoding. It has no on board tuner. It has no on board storage (other than a little flash for firmware). It needs the computer to store what it spews out, otherwise it's just wasted electrons. It needs the external material provided via component, S-video, composite video, optical sound, or stereo.

Do we know for sure that SageTV, BeyondTV, and GB-PVR got pre-release units? Perhaps all they got were the communication specs for the HD PVR. (ie commands to set recording format, send IR Blaster commands, start recording, and whatever was needed to accept the raw stream from the box).

(When I originally wrote this last night, I couldn't post it due to my net connection going down. I now have the answer to my own question via another post. In Brent Evens "Geek Tonic" Blog he says, "I've heard from representatives of SageTV and Snapstream (BeyondTV) and both of them seem to be as ready for the device as possible, but word is Hauppauge is still working on the drivers to get them just right." In my mind that pretty definitively says neither Sage or Beyond have pre-production units.)

In other words they probably got similar stuff required for any other USB capture device. This box has NO tuner and is probably not that much different (other than the input connectors, encoder chip and blaster) than the Plextor ConvertX or Pinnacle Studio Moviebox Plus.

I've never seen anybody even suggest that a HD Homerun can playback recordings. It just tunes the station, and passes the raw data to the recording box, (though admittedly two at a time from it two tuners.) It's just another input device. The HD PVR is just that - a way to stream encoded video to the computer. Why would you expect it to be an output device?

It seems to me that a lot of people just look at the product name, and run off on a wild tangent of speculation. They've not read the reports from CES, the product specifications at the Hauppauge site, any of the lengthy discussions of it stretching back to about November.

As I said above, the HD PVR is not that far removed from other external encoding devices. It differentiates itself by two unique features. The first being component video input as opposed to the usual composite and S-video (though it has both of those too). The second being that it hardware encodes to H.264 and VC-1 as opposed to the usual Mpeg2. So no, it won't slice, dice and make julienne fries. It won't make a martini either. But it should be a damn fine way to encode Hi-Def, non OTA video -- the stuff normally encryped by our satellite and cable companies.

Also note that shipments have been delayed till mid May for the earliest orders, and end of May for later ones. I know someone will claim that as evidence that the product will never happen -- that the big media companies are squashing it. The stated reason in an email to people who have pre-ordered it, is that there has been a production delay in the plastic cases.

If you recall, at CES the anticipated shipping date was mid April. When that date was pushed back to May, it was because there were some design and production delays from their case manufacturer in China. On small run items, it is quite common for Chinese plastic molding companies to miss deadlines, or have initial quality problems.

The two shipping dates imply to me, that the demand was higher than they expected. That is, the first run of boards, was probably ordered and manufactured months ago. There are people who purchased in the first 24 hrs, whose order numbers fall in the second shipment block. Sure sounds like they needed to make more boards. It might also have required a larger run of the cases than the initial order, hence the delay.

Of course much of what I've said is my own speculation. With all the months of reading I've done on the Hauppauge HD PVR, these are conclusions that seem to make sense.

I actually seen this before, i really believe they have the best quality of products

I have an HD-PVR here waiting for the release of Myth 0.22 (because it has HD-PVR support built into it). At present I've got a working R5.5 machine and I do not want to break it by trying the HD-PVR during the Mythtv 0.22 pre-release period.

For now, I've been playing with the HD-PVR in that OTHER OS. I've been able to get the HD-PVR firmware updated and Hauppauge software loaded, and even get a few hours of HD h.264 video recorded. I've got the HD-PVR connected to a Directv HD satellite receiver (outputting 1080i). For audio, I'm using a fiber optic cable for SPDIF audio. I've got dual core AMD processors in all my test pcs right now.

I have transferred some of the .ts files (recorded at 9MBits/sec and 13 MBits/sec) into the VIDEOS folder of my Knoppmyth box (running R5.5). My KM system uses mplayer to play videos from the VIDEOS folder doesn't work so well with these HD-PVR recordings. The video does not play at full speed (slow motion) and the audio is VERY delayed. Also, mplayer stops playback after about 10 seconds.

In Mythtv, what player are the rest of you using to play back these h.264 files recorded with the HD-PVR? Are you using mplayer or the Mythtv Internal Player?

I've tried playing the HD-PVR files in Windows XP with poor results. Playback never takes up the full dual core CPUs. I usually see 50-70% CPU usage.
mplayer (all flavors I've tried) gives slow, jerky playback, with audio, and it crashes after about 10-20 seconds of playback.
VLC Player plays with many dropped frames, also with audio, but it never crashes. I see what I estimate as about 1 frame per second, with 29 frames dropped in between those single frames.
I get fairly smooth playback, with good audio sync if I use Hauppauge's WinTV7 application for playback.
I also get fairly smooth playback with good audio sync if I use Cyberlink's Power DVD 7.3 for playback.
The pattern I'm seeing is that open source video players do not play HD-PVR recordings well at all.

What are you users of the HD-PVR seeing in Mythtv?
And what player gives smooth playback?

In 0.22, software decode uses multiple cores. And, you can get accelerated playback with VDPAU (if you have a supported nVidia graphics card). VDPAU decode has been quite stable for a while now and has no problems with HD-PVR recordings. It will also play blu-ray content (raw file since it does not understand the ISO format yet), but the audio can sometimes give you problems.

In fact, my Win7 machine using the native Win7 accelerated decoders performs about the same as using VDPAU on the same hardware. Windows is a real pain about configuring codecs such. It all just either works or not under MythTV. The latest ffmpeg syncs into 0.22 have really improved both performance and codec support.

Both the Internal player and mplayer handle the h.264 files fine. Of course it's really VDPAU doing the heavy lifting but the R6 mythtv-svn and installed mplayer are VDPAU enabled. Both play my HDPVR files and bluray rips nicely. I have a $50 8400GS/512M nvidia card in all of my clients.

Are you saying that VDPAU is necessary to get smooth h.264 playback in Linux? Or is Mythtv 0.22 code the key?

Can you easily turn off VDPAU and let us know how well h.264 playback goes?

As I understand it, VDPAU only works with newer (higher numbered) nvidia chips (8800GTS and higher - with the 8400GS being the exception).

What happened to XVMC? Was it abandoned? Three years ago, XVMC was promised to be THE hardware acceleration, wasn't it?

For my Mythtv computers, I'm using the onboard nvidia 6150 display chips. The 6150 chip is HDTV capable and displays 1920x1080 images just fine. I've been watching and recording HDTV for the last 3 years using them.

MythTV 0.22 has h.264 support. If you have the processing power, software playback of h.264 is great. I used software decode before VDPAU was available/stable and it worked fine on my Core2Duo, but took up most of the CPU. If you have a couple year old CPU or have a frontend/backend combo machine, I would suggest you buy an nVidia board which supports VDPAU.

To do the decoding in software, both cores have to be used. There was work done in ffmpeg to do just this but as far as I know it was just experimental. It's called ffmpeg-mt (for multi-threaded).

So the question is does myth and/or mplayer built on R6 use ffmpeg-mt. Unfortunately I don't know, perhaps Mr Harris knows.

On my old R5E50 (yeah really old) before I upgraded to R6, I used a commercial product called CoreAVC. It's actually a windows driver that can be used by mplayer. It was the only way I could play bluray rips in software.

When recorded inside Mythtv, what file extension is on the files generated by the HD-PVR? Are they .ts files?

How do you control the datarate of the HD-PVR recorded files? Is it a new screen in the Mythtv setup screens?

They are .mpg files. You control the datarate by setting up a "recording profile". They have reasonable defaults so you don't have to setup a profile but I did. I maxxed out the bitrate because thats what I want. File size for a program "Ghost Lab" on TDCHD via satellite at 720p is about 2.6G. That show is an hour long.

They are .mpg files. You control the datarate by setting up a "recording profile". They have reasonable defaults so you don't have to setup a profile but I did. I maxxed out the bitrate because thats what I want. File size for a program "Ghost Lab" on TDCHD via satellite at 720p is about 2.6G. That show is an hour long.

Cool. Thanks for the info.

My test recordings (made in XP) using the Hauppauge software are .ts files. That's what you get when you select AVCHD as your video file type.
For the last couple of days, I've been recording Star Trek Enterprise off of the HDNET channel (1080i) at the max datarate of 13MB/sec. I've also done some test recordings at 9MB/sec for comparison.

It appears that the 13MB/sec recordings take less CPU power to play back than the 9MB/sec recordings do. Did you notice the same thing?

It appears that the 13MB/sec recordings take less CPU power to play back than the 9MB/sec recordings do. Did you notice the same thing?

To tell you the truth I didn't check! Using VDPAU the CPU usage is very low. Just happy it plays it with no problem. It's interesting that you are seeing that though. Seems like it would be the opposite.

The CPU usage makes sense to me. The 13MBit/s datarate files are compressed less than the 9MBit/s files are, which is why the final files are bigger. Since the 13MBit/sec files have less compression, the CPU doesn't have to work as hard to decompress them.
So, it follows that the 9MBit/s datarate files use more CPU power on playback - more compression used to make the file smaller and thus more CPU power needed to decompress it for playback.

I just wondered if other people noticed the same trend - which would confirm my theory of CPU usage.

About a year ago before I upgraded hardware I tried playing some HDPVR video that people had posted and I had downloaded. It seems to me the lower bitrate files were "more playable" than the high bitrate ones were. Looking back on that now I may have been confused. It might have not been a video problem but an audio one. I recently played one of my HDPVR files with mplayer and it did not play properly. It had to do with the audio encoded AAC. Obviously I didn't have mplayer configured right. Instead of futzing with it I set the HDPVR to do AC3 instead and all is good.

As I mentioned, in my current R5.5 system (with a nvidia 6150 display chip), mplayer plays back these recorded h.264 files as chunk...chunk...chunk. (The video does not play at full speed (slow motion) and the audio is VERY delayed. Also, mplayer often stops playback after about 10 seconds)

What about updating mplayer and ffmpeg to the latest svn versions? Will doing that give better h.264 playback results by offering dual core support for mplayer?

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